The thermal gel pack as disclosed herein is capable of various uses, such as to warm the hands or to warm or cool an injured or painful part of the body.
In use the pack or envelope to be utilized as a hot compress has been placed in hot water, however this procedure of heating the gel pack has not been entirely satisfactory from a stand point of thermal efficiency and convenience of use. As the pack attains the temperature of 212.degree. F. thereby requiring tongs or the like for removal from the boiling water and the pack, being wet, is undesirable for its intended purpose, and requires drying thereof prior to use.
In addition heating of the water to the boiling point requires a fairly long period of time as distinguished from the significantly shorter time of heating of the pack by microwave energy as the pot or container for the pack must be fairly large for accomodating the pack without the pack touching the usual metal sides of the pot which would melt and damage the plastic envelope of the pack. This size pot would necessitate utilizing a large quantity of water thereby requiring a longer period of time for heating the water to its boiling point. Furthermore, when heating a gel package in boiling water in a pan or pot on a heater unit, the pan would be at the highest temperature which would damage, as by melting the plastic, present packages as the operator has no control over the pan temperature. Additionally when utilizing a large pan containing a large volume of water, the gel pack contacted the sides and bottom of the pan which were at a higher temperature than the water thereby resulting in damage to the envelope of the gel pack.
To overcome these deficiencies, applicant heats the pack by microwave energy in a microwave oven, however, the prior art gel envelopes were found to be entirely unsatisfactory since the thin plastic material utilized in the fabrication of the envelope developed pin holes in the plastic thereby resulting in discharge of the gel therefrom. Other deficiencies of the prior art envelopes are set forth below. To overcome the inadequacy of the compositions of the envelopes of the prior art applicant has invented a novel gel pack.